1. Field of the Invention
This invention relates to cosmetics for use in hair treatment, more particularly to a hair cosmetic composition using a specific type of ester compound or hydroxypropyl-etherified glycolipid ester.
2. Description of the Prior Art
As is well known, hair cosmetics are generally incorporated with a plurality of ingredients called a moisturizer or an emollient in order to impart moistness and suppleness to the hair. Those ingredients which have remained deposited on the hair have hygroscopic action and serve to prevent the moisture from evaporating or escaping from inside of the hair, and therefore, are effective to keep a moisture content in the hair substantially constant and also to bring an agreeable touch to the hair. There have heretofore been used as the moisturizer polyols such as glycerine, propylene glycol and the like and peptides or amino acid derivatives such as collagen, sodium pyrrolidonecarboxylate and the like, and as the emollient hydrocarbons, higher alcohols, higher fatty acids and esters.
However, when the moisturizer mentioned above is added to a hair cosmetic such as a shampoo or rinse which requires washing after its application, it is difficult to have the moisturizer left on the hair due to its solubility in water. On the other hand, the emollient also shows a reduced tendency of remaining on the hair if used in small amounts. Use of the emollient in large amounts allows for increased deposition of the ingredient on the hair which in addition supports a good water retention ability. However, when added, for example, to a shampoo in large amounts, the emollient adversely affects the detergency of the shampoo, with the results that the shampoo not only loses its inherent properties, but also becomes oily and sticky to the touch. Consequently, the emollient is of inferior quality and performance in exhibiting an improved hair setting or redressing force or ability.
In order to impart a setting force to the hair, polypropylene glycol butyl ester and its phosphoric ester have been employed which are generally formulated in hair liquids for men. However, these compounds lack a sufficient hair setting force when used in small amounts. Large amounts increase such force to a proper degree but involve a disadvantage that the liquids feel sticky and are liable to adsorb dust and are finally hard to wash away.
Another type of ingredient useful for the purpose of setting or redressing the hair is a film-forming polymeric material such as methacryl-acrylic acid copolymer, polyvinylpyrrolidone or a vinylpyrrolidone-vinyl acetate copolymer. The polymeric material has been practically used, for example, in set lotions, hair sprays and similar cosmetics for women. When used in small amounts, such polymeric material is insufficient in the setting force, whereas large amounts are disadvantageous, though the setting force is improved, in that the polymer film becomes hard and objectionably stiff to the touch and is difficult to wash away such as with a shampoo.
In view of that situation, the present inventors have made intensive studies on a wide variety of compounds which can surmount the defects of the prior art cosmetics. As a result of these studies, they have found that a particular hydroxypropyl-etherified glycolipid ester compound meets with the desired properties and gives the best results. Based upon this finding, the present invention has been accompalished.